67 Lightwin piston rings

[JasonAych]

Re: 67 Lightwin piston rings

Silencer there and screen there as well. By the plug chops I've done I would say it is definately running rich in the higher rpms. Plugs are black.

Don't think so with the air leak. I used a propane torch with no flame. Went around all the seal points including the crank case. Trick I learned some time ago. If anything will find a leak, propane will.

I am going to focus on the plug wire theory. I just has a better look at them. I actually think someone replaced the coils (not too long ago) and used the original wires. How f'd up would that be. The boots are a bit dry rotted and wires don't look great either and there is that one tiny chunk missing right near the boot behind the side cover. I have brand new 5 strand copper core 7mm wires. I have 2 lengths that are perfect for the job. I just have to find some nice boots. I am sure NAPA will have something, hopefully.

I'll let you know how it goes if I make it. My wife has been taking notice of how much time I have into this job and could have been spent working on the bathroom we are remodeling

 

[JasonAych]

Re: 67 Lightwin piston rings

May have found the problem. I took it apart to replace the plug wires. Was in the process of puting it back togther when I notice the brass sync/link (as someone called it) had a broken leg so to speak. The weird thing is when it broke, it moved towards the carb which would open the carb too early, I'd suspect. This kind of lines up with it running better when I partially close the intake with my finger. It engages the crab as soon as the cam lobe reached it. Someone said it would be marked. The only marks I see are about 1/4 up the lobe and another about 3/4. Am I supposed to line the carb arm up with the one about 1/4?

I soldered and JB welded the leg back on. Waiting for it to cure. Will let you know how it goes.

Thanks for your help so far.

 

[JasonAych]

Re: 67 Lightwin piston rings

I'm changing the saying "watching paint dry" to "watching JB Weld cure". After hours of flipping the "throttle control cam" (aka sync/link back) and forth to keep the JB weld formed the way I wanted it, it finally set and is pretty much cured.

Where is a good starting point to position these cams? I don't really see any marks. There are 2 marks at about 1/4 and maybe 1/2-2/3 up the lobe. They look more like stains than marks though, but they could be. When the leg broke it kind of positioned it self forward and the cam engaged the throttle arm at the very tip. I believe this to be too soon.

I'd appreciate it if someone could tell me where to position it. If someone could take a look at a good runner (lightwin) and let me know how far up the cam it first engages the throttle arm that would be great! Approximately would be good, an actual measurement would be great!

If not I guess I can do some trial and error with it.

 

[kbait]

Re: 67 Lightwin piston rings

I just looked at my 63 johnson 3hp (same deal), and the follower (probably wrong term) first hits the cam about 1/4" from the end (low speed side of the cam..) when advancing the control handle. My motor runs great at all speeds, no hesitation to higher rpms, but doesn't pump water after impeller change, so I didn't run it too long. I think I was in error telling you there's a mark on the cam. I don't see one on mine. I don't remember them being ultra-sensitive to the exact point of contact, but I've always had 'em 1/4" or less. Hope that helps, and I hope it runs right soon! I know this current 3hp I've been fiddling with will make me about $2/hour upon selling .. It's been one of those 'one thing after another' deals. It's dented, and ugly, and it's GONNA run and pump water, dammit..haha

 

[JasonAych]

Re: 67 Lightwin piston rings

Another concern I have is with the prop. I know these weedless props look funny but I can't help feeling the blades are bent/curled backwards. I wouldn't have the faintest idea how to ask someone to measure the blades. On the positive side, both blades are consistent. There are some tiny gouges but nothing serious enough to make me think what ever caused the gouges caused the blades to bend.

 

[kbait]

Re: 67 Lightwin piston rings

Maybe it's just the funky look that's got you. It'd be difficult to bend both of the prop blades exactly the same by accident.. I had a similar 5hp prop that indeed had one of the blades bent backward, so it is possible. I brought it to a local prop guy (garage shop) and he bent it correct for $5 (no clean-up or paint). I would think once you get it in the lake, you'd know for sure..

 

[jshouk]

Re: 67 Lightwin piston rings

i have a weedless prop on my 58 and it looks just the same; in fact i looked at it today and had the same thought you did. blades have no damage. jon s

 

[JasonAych]

Re: 67 Lightwin piston rings

Well after all that there is improvement.

Seems to rev up better but still sputters a bit. I am going to see if I can locate a plastic float and set the float level. I am out of ideas after that.

Keeps you posted. Thanks for your help so far!

 

[JasonAych]

Re: 67 Lightwin piston rings

I'd appreciate help on finding a non-cork float for it. It's a 67 Lightwin. I've looked around and can't seem to locate one.

 

[kbait]

Re: 67 Lightwin piston rings

The float is the same from 3hp-at least 18hp for many years. BRP part number should be 0396514 for the non-cork float alone, or get a kit from BRP and it will have the same float included. I don't have that number offhand, but your JohnnyRude dealer, local marina, will. Even though you think all the gaskets are good on your carb, going with the kit makes sense, and not too much more $$.